U.S. Pat. No. 4,787,326 describes such a sewing machine with the transmitting ratio of the two partial transmission units being in each case 1, i.e. the input end gears and the output end gears of each partial transmission unit have the same diameter or the same number of teeth. Due to the arrangement of the partial transmission units the constructional depth of the rotary housing relative to its axis of rotation is comparatively large. As a consequence the moment of inertia is comparatively large, which, in turn, leads to the fact that the acceleration of the rotary housing requires corresponding turning moments from the side of the drive.
In the case of the known sewing machine the drive of the needle bar is effected by means of a crank drive structured as a needle bar drive, with a thread feeder drive being in turn deducted from the crank pin or crank link of the needle bar drive. This, too, serves to increase the constructional depth of the rotary housing--relative to its axis of rotation--and thus the moment of inertia of the rotary housing.
Sewing machines with rotary housings and comparable in terms of kinematics are known from German patent 20 23 186, U.S. Pat. No. 4,574,718, U.S. Pat. No. 4,553,489 and U.S. Pat. No. 4,594,954.